JohnCh

ECU sets ignition timing. Cam timing, which determines when the valves are at full lift in relation to where the piston is in the cylinder, is mechanical. Call Web Cams on Monday to discuss the numbers you found and see if they can help. However, given the note in the build sheet about 3 cam combinations, it's possible that the intake is not from them as identified in the ECU. -John

Lining up the the slots on the back only works for the stock cams or aftermarket cams that were specifically ground with that setup in mind. The latter is not a standard (e.g. Kent, who is a major supplier of high spec cams for Zetecs and Duratecs, does not do this). Based on the ECU information, you have a stock exhaust cam and a Webcam intake. I've dealt with Webcam before after finding a pair of their cams in a used head. They keep good records and using the number engraved on the cams were able to find the specs for them even though they were a custom grind done many years earlier. Find the number, call them, get the specs to understand what you have. I'd also closely examine the exhaust cam to make sure that ECU notation is correct and they are stock. A challenge you face is not knowing exactly what the comments on the ECU info page really mean. Does "advanced intake and exhaust cams 5 degrees" mean 5 degrees from stock cam timing for both sides or from the specs provided by Webcam, or something else? Was that change based on a recommendation from an engine builder, the shop that supplied the cams, a guess, or established on the dyno? I'm a little (okay, a lot) anal. To be safe and to really understand the starting point, I would get a hold of a good quality dial indicator and holder and establish the existing timing before you release the cam belt. You will need these tools anyway when reinstalling the cams. Note: if your plan upon reassembly is to have the cam timing optimized on the dyno, then you could take accurate measurements of the slot angle of each cam and use this for reassembly rather than the dial indicator. It will be safe from the standpoint of valves meeting pistons and should be a good starting point for the dyno operator, provided that person is competent in that area -- that is not the case for all of them. -John

Road & Track just published an article about this epic journey: https://www.roadandtrack.com/car-culture/a37026916/ross-robbins-cross-country-lotus-elan/ -John

For some reason, some photos don't respond to the hack of rotating them in the native Windows Photo viewer. I had to use MS Paint, which did the trick. Now back to our regularly scheduled problem solving and upgradeitus programming... -John

Thanks Andy. The shop with the hub dyno is the one I initially planned to use to dial in the engine -- the operator really seems to know his stuff -- but COVID restrictions made that tough. VRM filled the gap since my only concern at this stage was confirming timing at full throttle. Drivability/part throttle mapping was done on the road through logging and the Emerald's adaptive, closed-loop function and is fine, so VRM's lack of a load-based dyno wasn't an issue. However, for the new 2.4L engine in the Caterham, I won't have the luxury of a baseline map that is close and will have the hub dyno shop map that engine. Getting a baseline of my current engine on their dyno would allow an accurate comparison of the torque curves between the two engines. Unfortunately CarbConn has never met my expectations over the years, and this trip was no different. First, they didn't bother to clean the big pool of coolant and gearbox oil on the floor from a car that went earlier that day. On the surface, not a big deal, but to me it's a lack of attention to detail. How are you supposed to know if your car is dripping during the runs when the floor is like that? Second, the runs were all problematic. The fourth gear run had the sine graph issues. Not necessarily their fault, but annoying nonetheless. The next run in third gear was fine aside from the apparent wheelspin. During the next run, the engine stopped pulling at 6000rpm because they hadn't released the dyno brake (or at least that's what they told me) and on the fourth run, they forgot to hit record. I could have gone for a fifth run, but decided to cut my losses. It's a shame because they are the biggest facility in the area and have a recent 4 wheel Dynojet. -John

I'm not shopping for numbers. I was simply curious how the older VRM dyno would compare with the newer one at CarbConn. I didn't go to the latter first because I don't have confidence in their ability to tune a car based on prior experience, but I do have confidence in VRM. The reason I'm now considering the shop further away with a hub dyno is not to see if the numbers go up, but if my hypothesis about wheelspin is correct. Although I don't expect numbers to be the same from one dyno to another, I do expect the torque curves to have very similar shapes. That's not the case here and it makes me curious. -John

Looking more closely at the two dyno graphs as well as previous ones from a Mustang dyno with stock pistons and Kent DTEC10 cams vs. the new DTEC20 cams, I think I may know what's going on. The CarbConn graph is much flatter between 4300rpm and 7000rpm than the other graphs, and it doesn't peak until about 7000rpm vs. 5500rpm. Although I said there was no wheelspin during the third gear run, I'm wondering if there was a little? That would explain why the numbers on both graphs only differed by a couple of lb-ft at 4300rpm and 7000rpm, but the rise that happened between those two numbers in the other graphs were absent from the CarbConn results. Perhaps I was simply hitting the limit of torque the tires could transfer to the rollers during that range? The dyno operator at VRM could feel the wheelspin in third and I could see it while standing behind the car. At CarbConn, I was driving -- and have no experience doing dyno runs so easy for me to miss that slight sensation -- and no one was looking at the tires to confirm no slip. Judging by the seat of pants, the shape of the VRM torque curve also feels more accurate. There is a DynaPak hub dyno about an hour away. I may book time there to see what they show given their system eliminates the possibility of tire slip. -John

No idea. The torque doesn't feel less than the old engine with milder cams and lower compression ratio. That engine on a Mustang dyno registered 145 ft-lb, so consistent with the readings from VRM's dyno. Perhaps doing it in third gear lead to more parasitic losses than fourth gear which is 1:1, but that wouldn't explain the differences over 6700rpm. To me this simply shows that comparing dyno numbers gathered from different dynos is inconclusive. -John

Here is a picture that shows the pressure cap and thermostat housing so you can see how they work together. Regarding the tube in the overflow tank, it's best if the end is cut at an angle to ensure that it doesn't' seal against the bottom and prevent the flow of coolant under suction. -John

Hmm an (apparently) organized speed event with no helmet requirement. Must be a country with very few attorneys. -John

I took advantage of some downtime and booked a session at another dyno facility to compare their numbers to those achieved a couple of weeks ago at VRM. My assumption was this other facility, with a much newer Dynojet would produce higher numbers, but I was only partially right. Peak power was up to a bit over 189 vs. 184, but the entire torque curve was shifted downward except for the top end where it increased. In fact peak torque was fully 12 ft-lb lower today, but the torque falloff over 6700rpm was less severe, resulting in power increasing all the way to 8200rpm vs. flat from 6700-8000rpm in the original dyno session. Weather was nearly identical both days, the only differences were the Dynojet versions and the fact today's run was done in third gear vs. fourth at VRM. VRM tried third, but there was a lot of wheelspin. We tried fourth today, but the pull was taking too long and resulting in a really, really wavy trace that looked like a sine wave. Third gear today seemed wheelspin free. -John

I think that is a pressurized system. Raceline uses the same thermostat housing in its water rail. It's designed so the overflow port which feeds the expansion bottle is only open to the system when the pressurized cap hits it's limit and the base retracts. Otherwise it is sealed. -John

Did you see the trailer @Brightonuk has for sale in FL? -John

I've dealt a lot with Raceline over the years. Peter knows his stuff. I'm sure it will be a fantastic engine. Calling @Vovchandrin case your engine does go up for sale and his engine issues prove insurmountable. -John

Please keep the details (cam specs, dyno sheets, etc) coming. This will be fascinating to watch. From the comments it sounds like Raceline is building a new engine in the UK, then shipping it over? If that's the case, are you keeping your current Zetec as a backup or selling it? -John

Welcome Gavin! Have you had a chance to put any miles on it yet? -John

Not sure why your photos are attaching that way. They are uploading as .heic files which is an Apple-specific image file format, but when testing an upload from my iPhone which is set to that format, images work correctly. You may want to try again or save the photos as a .jpeg first, or PM me and I'll see if I can help. -John

Look at the bright side. You may not excel at fixing cars quickly, but you are very good at breaking them -John

Thanks for the feedback. Your example is for Xenforo, however, we are on Invision so the capability and available plug-ins don't necessarily apply. Currently the main page is set to the forum view as that's the primary reason the site exists. That may change in the future if we spin up the club aspect again, and if it does, it will focus on highlighting all content and membership benefits, not just the galleries. Specific to showing random photos, the current native option for the Galleries page does not work well and tends to draw from a very small group of the same photos. i.e. not very random. Invision hints that this might be fixed with the new release. If it is, I will investigate enabling it when we do that upgrade this summer. Although there may be a third-party plug-in that works well, the more plug-ins we have, the more potential for bugs and issues when doing future upgrades. That's an acceptable risk when it's a for-profit forum run by people who do this for a living and have the time and skillset to troubleshoot quickly and effectively. That's not the case here. For now, we are optimizing on keeping the forum working well and current. -John

I don't follow the gif argument since it is intended as a single user feature. A rating feature only has value if a number of people are supplying the ratings. If only two people rate a topic and both have an issue with it or the thread starter, and give it a 2, does that mean it's a bad thread and people should skip it? Unfortunately, the forum software only shows the rating average, not the number of ratings supporting the number. It's a poor implementation for decision making. The reason this question is even being raised is because your thread on your engine issues only had a 3.5 star rating even though the consensus from posts in the thread is that's it's been worthwhile reading. There may be a sub forum setting for the rating feature that isn't turned on for the help section. -John

The forum software comes with a topic rating feature at the top right of each thread that allows a viewer to rate the thread on a scale of 1-5 stars. A quick count of the last 60 posts in the General and Technical Forums, shows only 3 threads have a rating. Because it is used so infrequently, it's likely true that those threads with ratings are based on input from a very small group of users. This means a single low rating, whether intentional or inadvertent, will dramatically effect the rating. Also, the sample size is too small to have any real value. Personally I don't see the benefit of a rating system in a forum like ours which only has a handful of new threads each day, so my preference is to turn it off, but before I do, I thought I'd let folks weigh in via the polling option. -John

I just gave him a 5 which bumped it by about 1/2 star ( @Vovchandr where do I send the PayPal request?). This tells me very few people have rated it thus far, so if someone hovers over the stars to see if it will show more detail like Amazon has trained us to expect, and accidentally clicks over the first or second star while doing so, we'll see swings like this. The only way to avoid this is by disabling the feature. Personally, I don't see much value in a thread rating on a forum like this and a quick count shows only 3 of the last 30 threads in the General forum have been rated -- interestingly two of those were started by @Vovchandr. Hmm... I don't think disabling it will be missed. I'll start a poll late to get input. Now back to Vlad's possessed engine. -John

@Vovchandr I think what @Croc means is: -John

@Vovchandryou won't know what you need to replace until you start taking things apart. This is particularly true in your case given the history of various engine-related maladies. Based on your comment that you are a few weeks away from pulling the head, I'd start thinking long and hard about your budget and determine if you approach this experience simply as a painful repair, or as an upgrade opportunity. If it's more than the head gasket, things can spiral out of control pretty quickly if you let them, so good to apply some rigor up front to define your desired end state and how much you are willing to deplete your kids' college fund to get there. Also, remember that if you make any performance changes -- and swapping to a higher flowing head is a performance change -- you will need to remap the ECU. Given the Pectel is pretty old and requires a version of Windows that is literally from last century, I'd give serious consideration to getting something more modern as part of this experience. -John

Well that progressed quickly! Sounds like you will end up with a beast! -John